There are many machines in our life that support our daily life and work, among which cooling fans can be said to be a very important category. Cooling fans play a positive role in ensuring the normal operation of our machinery. Cooling fans can be divided into DC fans and AC fans according to different forms of power consumption. What are the differences between them? Just let me introduce it to you.
One works differently:
The working principle of the DC cooling fan: through DC voltage and electromagnetic induction, electrical energy is converted into machinery to drive the fan blade to rotate, and the coil and IC are constantly switched, and the induction magnetic ring drives the fan blade to rotate.
Working principle of AC fan: driven by AC power supply, the voltage will alternate positive and negative, and it does not rely on circuit control to generate a magnetic field. The frequency of the power supply is fixed, and the changing speed of the magnetic pole generated by the silicon steel sheet is determined by the frequency of the power supply. However, the frequency can not be too fast, too fast will cause difficulty in starting.
The second structure is different:
The rotor of the DC cooling fan includes the DC cooling fan blade, which is the source of air flow, the fan axis, which is used to support the rotation of the balanced fan blade, the rotor magnetic ring, the permanent magnet, the key to promote the switching speed of the magnetic stage, the outer frame of the magnetic ring, Fixed magnetic ring. In addition, it also includes supporting springs, through which the nodules are fixed to rotate the entire component, the motor part, the production of the direction of rotation, and the speed of the active size and rotation are critical. It has good speed regulation performance and simple control.
The internal structure of the AC fan (single-phase) is composed of two coil windings, one is the starting winding, and the two windings are connected in series with each other, thus forming three points, the series point is the common terminal, and the end of the starting winding is the starting terminal. The end of the winding is the running end. In addition, a starting capacitor is required, usually with a capacity of between 12uf and a withstand voltage of 250v. There are two connectors, one is connected to the end of the starting winding, and the other is connected to the end of the running winding, forming a delta type, The power supply (it is not necessary to distinguish between the live wire and the neutral wire) is connected to the end of the running winding (that is, it is also connected to one end of the capacitor), the other is connected to the common terminal, and the ground wire is connected to the motor casing.
The three materials have different characteristics:
Material of DC cooling fan: It is made of alloy material, which can be used continuously for more than 50,000 hours. The internal structure of DC includes transformer and main control board (including frequency conversion circuit, rectification filter, amplifier circuit, etc.) Long service life.
The internal structure of AC fans is mainly based on transformers. Most of the materials used for AC fans are made of domestic discharge needles, generally tungsten needles or stainless steel materials. If the voltage fluctuates too much, it will affect the service life of the transformer.
Traditional AC fans, the speed of the AC motor is particularly high, and it is not suitable for double-layer fan blades. Once the motor speed is reduced, the working noise will be particularly loud and the vibration will be very serious. Therefore, to restore natural wind with double-layer fan blades, a more stable and controllable DC brushless motor is used. Compared with AC motors, DC motors have the obvious advantages of adjustable speed, low noise and high energy efficiency when the fans work in low gears. Therefore, with the double-layer fan blade design, the fan can achieve a gentle wind like natural wind.
